2 of 9 Hexaflumuron FINAL WORK PLAN

Introduction:

This is the Environmental Protection Agency’s (EPA’s) Final Work Plan for the registration review of hexaflumuron. This work plan includes the expected registration review timeline. The work plan also addresses public comments received concerning the Preliminary Work Plan (PWP) in the Summary Document , which was posted in the hexa flumuron registration review docket (EPA-HQ-OPP-2009-0568), and any other co mments concerning the initial docket postings. The Summary Document provided information on what EPA knows about the pesticide and what additional risk analyses and data or information the Agency believes are needed to make a registration review decision.

The Agency is implementing the new registra tion review program and will review each registered pesticide every 15 years to determin e whether it continues to meet the Federal Insecticide, Fungicide, and Rode nticide Act (FIFRA) standard for registration. Changes in science, public policy, and pesticide use practices will occur over time. The registration review program is intended to make sure that, as the ab ility to assess risk evolves and as policies and practices change, all registered pesticides contin ue to meet the statutory standard. The public phase of registration review begins when the ini tial docket is opened for e ach case. Information on this program is provided at: http://www.epa.gov/oppsrrd1/registration_review/

.

Hexaflumuron is a benzoyl-phenylurea termiticide re gistered for use to control all economically important species of termites. It is registered for use in a bove- and below-ground termite bait station systems in food and nonfood areas. Treatme nt sites may include interior and exterior surfaces of buildings and crawl spaces, fences, utility poles, decking, landscape decorations, trees, and other features whic h could be damaged by termite foraging and feeding activity. Hexaflumuron is approved for use in indoor reside nces. While it is not a restricted use product, hexaflumuron is sold in conjunction with a serv ice provided by pest-con trol operators licensed by the state to apply termiticide s. As hexaflumuron was firs t registered in 1994, it was not subject to the reregistration pr ocess as required by FIFRA.

Comments Received on Preliminary Work Plan:

The Agency received two comments on the Hexaflumuron Preliminary Work Plan during the 60 day comment period that was open Septem ber 23, 2009 to November 23, 2009. The FIFRA Endangered Species Task Force (FESTF) comme nted on data compensation matters. Dow AgroScience (DAS), the technical registrant, responded to inform ation requests specified in the PWP, provided error corrections, and commented on the anticipated ecological fate and effects data needs. Response to comments relating to human health comments on the hexaflumuron

PWP are addressed in a se parate document entitled Hexaflumuron Public Comment Regarding the Health Effects Division’s Human-Health Assessment Scoping Document in Support of Registration Review of 12-AUG-2009 (D362321). Response to comments relevant to the required ecological risk assessment for hexafl umuron are addressed in a separate document

entitled EFED Response to Comments on the Problem Formulation for Hexaflumuron (D362322). An overview of comments is presented in the “Summary of Comments and Agency Responses” section of this document. A more de tailed description of the comments received and3 of 9 the Agency’s response to these comments is ava ilable in the separate response memoranda from the Agency’s Environmental Fate and Effects Division (EFED) and Health Effects Division (HED) located in the hexaflumuron docke t (Docket ID EPA-HQ-OPP-2009-0568).

Risk Assessment and Data Needs:

Environmental Fate and Ecological Risk:

• The Agency has not conducted a risk asse ssment that supports a complete endangered species determination. The ecological risk assessment planned during registration review will allow the Agency to determine whether hexaflumuron use has “no effect” or “may affect” federally listed threatened or endangere d species (listed species) or their designated

critical habitats. When an assessment conclude s that a pesticide’s use “may affect” a listed species or its designated critical habitat, th e Agency will consult with the U.S. Fish and

Wildlife Service and/or National Marine Fisher ies Service (the Servic es), as appropriate.

• Please refer to the February 17, 2010 document, EFED Response to Comments on the

Problem Formulati on for Hexaflumuron (D362322) in the registration review docket (Docket ID EPA-HQ-OPP-2009-0568), for a deta iled discussion of the anticipated ecological risk assessment.

• Based upon comment received on the PWP, the Agency has decided the following studies will not be needed to support hexaflumuron registration review:

o (GLN 835.1230 and 835.1240) Leaching and Adsorption/Desorption Mobility Study

o (GLN 835.4100) Aerobic Soil Metabolism Study

o (GLN 835.4200) Anaerobic Soil Metabolism Study

• Based on the Agency’s review of the available ecotoxicity and environmental fate data for hexaflumuron, the Agency will issue a data ca ll-in for the following data to support an ecological risk assessment for he xaflumuron registration review:

o (GLN 850.2300) Avian Reproduction Tests (waterfowl and upland game species)

o (Special Study) Acute Oral Toxicity to Honey Bees

o (GLN 850.4100) Seedling Emergence (Tier I)

o (GLN 850.3040) Field Test for Pollinators. The Agency notes that these data may be required in the absence of information indica ting exposure to pollinators is negligible.

Human Health Risk

• Because of the low toxicity of hexaflumuron a nd the low-exposure scenarios expected from hexaflumuron products, a human health risk asse ssment has not been previously conducted.

• Given the current uses, the Agency does not anticipate conducting a human health risk assessment for hexaflumuron to support registra tion review. However, if in the future new uses or use patterns emerge, human health risk assessments that examine the dietary, residential, aggregate, or occupationa l risks of hexaflumuron may be required.

• Based on the Agency’s review of available hum an health toxicity and exposure data for4 of 9 hexaflumuron, no additional data are expected to be required to support registration review.

• Please refer to Hexaflumuron Human-Health Assessment Scoping Document in Support of Registration Review (D362321), located in Docket Number EPA-HQ-OPP-2009-0568 at www.regulations.gov for a detailed discussion of the Agency’s human health risk

assessment needs for hexaflumuron.

Other Data Needs

• (GLN 830.7050) UV/Visible Light Absorption – this study is a new data requirement under 40 CFR part 158 (Product Chemistry Data Requi rements) for registration of a pesticide (food and non-food uses). The Agency will issu e a data call-in for this study to support registration review.

Timeline:

EPA has created the following estimated time line for the completion of the hexaflumuron registration review.

Registration Review for Hexaflumuron Projected Registration Review Timeline

Milestone Estimated Date Opening the Docket Open Docket & Public Comment Period fo r Preliminary Work Plan Completed Sep.

2009 Close Public Comment Period Completed Nov.

2009 Case Development

Final Work Plan Mar. 2010

Issue DCI Oct. – Dec. 2010

Data Submission Oct. – Dec. 2012 Open Public Comment for Preliminary Risk Assessment Apr. – Jun. 2014 Close Public Comment Period Jul. – Sep. 2014 Registration Review Decision Open Public Comment for Proposed Regist ration Review Decision Oct. – Dec. 2014

Close Public Comment Period Jan. - Mar. 2015 Final Reg Review Decision and begin post-decision follow-up 2015

Total 6 years

Summary of Comments Receive d During Docket Opening:

Summary of Comments on Anticipated Data Needs

DAS Comment: DAS commented that a study to dete rmine the anaerobic soil metabolism should not be required since exposure of hexaflum uron, via the termite bait system, is unlikely to

occur in anaerobic soil conditions. DAS informed the Agency that data are available to5 of 9 demonstrate that hexaflumuron degrades more rapidly under anaerobic conditions than under aerobic conditions; and, that whil e moderately persistent in so il under aerobic conditions, the formulation, packaging/delivery of hexaflum uron significantly redu ces any quantity of hexaflumuron that may enter the soil environment.

EPA Response: The Agency agrees that the hexafl umuron will not readily degrade in aerobic or anaerobic soils, therefore reducing the need for certain fate data on hexaflumuron.

3⁄4 The Agency has modified its anticipated data needs to exclude the following OPPTS guideline studies: 835.4100 (Aerobic Soil Metabolism) 835.4200 (Anaerobic Soil Metabolism)

DAS Comment: Based on the chemical and fate charact eristics of hexaflumur on that show it to be relatively immobile, DAS believes the leachi ng and adsorption/desorption studies identified as anticipated data need s should not be required.

EPA Response: EPA agrees that hexaflumuron is not like ly to be mobile in soils, therefore reducing the need for certain fate data on hexaflumuron.

3⁄4 The Agency has modified its anticipated data needs to exclude the following OPPTS guideline study: 835.1230/1240 (Leaching and adsorption/desorption).

DAS Comment: In its comments, DAS referenced multip le ecological toxicity studies that it believes may be relevant to fulfilling identified data gaps.

EPA Response: The Agency appreciates DAS’s offer to make available hexaflumuron data that has not been previously submitted. While EPA will not modify its current ecotoxicity data needs at this time, the Agency will review the data liste d below to determine if the data can be used to satisfy the identified data gaps for hexaflumuron.

3⁄4 The Agency requests DAS submit the following studies: Cole, J. H. The Acute Contact and Oral Toxicity To Honey Bees of XRD 473. Unpublished report of Dow AgroSciences DET 645, 02-SEP-1985.

Hakin, B., Anderson, A., and Chanter, D. O. The Effects of Dietary Inclusion of XRD 473 Technical on Reproduction in the Bobwhite Quail. Unpublished report of Dow AgroSciences GHE-T-184, 19 October 1988.

Hakin, B., Anderson, A., and Chanter, D. O. The Effects of Dietary Inclusion of XRD 473 Technical on Reproduction in the Mallard Duck. Unpublished report of Dow AgroSciences GHE-T-192, 10 October 1988.

Paterson, E. A., Toft, A. Evaluation of the pre-emergence phytotoxicity of

hexaflumuron in a herbicide scr een -2005. Unpublished report of Dow AgroSciences GHE-P-11276, 01-Dec-2005.6 of 9 3⁄4 The Agency also requests DAS submit the follo wing aquatic toxicity studies so they may

be evaluated and considered for future risk assessments: Thompson, R. S. XRD 473 Technical: Ac ute Toxicity to the Brown Shrimp. Unpublished report of Dow AgroSciences 1055, 29 March 1988.

Nozawa, T. and Annou, E. Acute Toxicity of XRD 473 to Suji Shrimp. Unpublished report of Dow AgroSciences GHF – R 159, 8 December 1988.

Maeda, M. and Funaki, K. Acute Toxicity of XRD 473 to Kuruma Prawn. Unpublished report of Dow AgroSciences GHF – R 157, 8 December 1988.

Jenkins, W. R., Jenkins, C. A., and O’ Connor, J. The Effect of XRD 473 on the Survival and Reproduction of Daphnia magna . Unpublished report of Dow AgroSciences DET 1153, 5 September 1988.

Smyth, D. V. and Thompson, R. S. XRD 473: Determination of Toxicity to the Green Algae Pseudokirchneriella subcapitata (formerly Selenastrum capricornutum )

. Unpublished report of Dow AgroSciences GHE-T-224, 19 August 1988.

DAS Comment: DAS provided comment(s) indicating the lack of potential exposure to pollinators and other [non-target insect] species to hexaflumuron. DAS noted that pollinators, such as honey bees, are not able to access the termite bait because it is located under ground and is confined within a bait cartridge whose sl ots are too narrow for honey bees to enter. Additionally, DAS noted that honey bees would not use the cellulose -based bait as a food source since bees have evolved to process pollen and nect ar as food sources. DAS also stated that the associated habitat of product use precludes potential risk to either pollinators or ground-dwelling

insects.

DAS commented that its a bove-ground product, Recruit ® AG (for which exposure to honey bees and other above-ground pollinators may exist), is not marketed in the US and, therefore, should not be included in the Agency’s ecological assessment.

EPA Response: The DAS argument that Shatter ® bait is located belo w ground and, therefore, unlikely to be accessed by pollinator species, appl ies only to above ground species, such as the honey bee. The Agency notes that there are seve ral species of non-target insects which are also pollinators that dig (e.g. native bees). The Agen cy believes that some species may consume the cellulose and that non-target insects may also be attracted to the sports-drink additive.

While DAS commented that its product design precludes potentia l exposure, EPA believes that DAS has not provided sufficient evidence to suppor t its case. EPA believes that information that indicated exposure would be pr ecluded would be helpful.7 of 9 3⁄4 EPA requests that DAS provide product design specifications, such as the diameters of

holes of bait stations used to house products containing hexaflumuron and their relationships to sizes of non-target insects. 1

The Agency notes that it must assess all potentia l uses unless a use is prohibited by the terms of registration. A risk assessment on DAS’s above-ground product, Recruit ® AG, will be conducted unless the product is e ither cancelled or the label pr ohibits use within the US.

DAS Comment: Regarding exposure to predatory sp ecies, DAS commented that non-target terrestrial animals and/or predator s are too large to gain direct access to the termite bait because they are excluded from the bait by the width of the slots in the bait station. DAS commented that termites tunnel below ground and are not expos ed above-ground unless as a member of the swarmer/alate caste. Therefore, termite predator s that may be exposed (secondary exposure) is limited to a narrow set that are primarily gr ound-burrowing mammals whose diet primarily

consists of earthworms.

DAS argued that above-ground termite predators cannot be exposed to hexaflumuron because

termite castes found outside of the colony have molted and, th erefore, cannot be carrying

hexaflumuron.

EPA Response: The Agency agrees with the DAS that non-target terrestrial animals and/or predators are excluded from direct exposure (acce ss) by the design of the ba it station. Therefore, non-target terrestrial mammals, bird s, reptiles and amphibians are onl y expected to be exposed to hexaflumuron through secondary exposure, i.e., c onsumption of contaminated termites (or other non-target insects).

The Agency notes that subterran ean termites sometimes form col onies above ground in locations

with sufficient moisture 2 . Therefore, non-target terrestrial animals (i.e ., mammals, birds, reptiles and amphibians) may consume termites above ground that are not in the alate caste (i.e., worker caste). In addition, the Shatter ® label states that the user should: “Identify critical areas suitable for placing termite stations. Critical areas include locations within or adjacent to visible termite activity such as: foraging tubes, termite infe sted plants, wood, and ar eas conducive to termite foraging (bath traps, moist soil in shaded areas, near irrigation sprinkler heads, roof down spouts and other moist areas, and near planting beds or other areas with plant root systems).” EPA suggests that if it is possible for the pesticide user to locate “visible termite activity”, then it may also possible for termite predators to capture those termites above ground.

The Agency also believes it is possible that term ites of all casts, includ ing alates, may carry a body burden of hexaflumuron that is not suffici ent to prevent molting and progression to the final life stages. To determine this, the Agency must understand the minimum hexaflumuron dose that is efficacious in termites. By way of illustration, a proposed steady-state concentration of 107 mg hexaflumuron/kg termite (calculate d using MRID 45516725) could be considered an

1 This request is voluntary and will not be required via data call

‐ in.

2 Suiter, D.R. Jones, S.C. and B.T. Forschler. Biology of subterranean termites in the Eastern United States. Ohio

State University Extension. Bulletin 1209. Access on line on 27 January 2010 at: http://ohioline.osu.edu/b1209/.8 of 9 efficacious dose, and also be considered a high- end dose which is not efficacious, i.e., an upper bound a body burden level.

3⁄4 The Agency requests DAS provide efficacy data to help determine potential body burden levels with respect to potential secondary exposure to hexaflumuron. 3

DAS Comment: DAS submitted with its comments, an assessment for secondary exposure (short-tailed shrew) with an estimated RQ = 0.92.

EPA Response: The Agency appreciates the analysis presented by DAS. However, the Agency notes that its approach for estimating exposures to mammals, as well as birds, reptiles and terrestrial-phase amphibians differs from that used by DAS, in that the Agency assumes a diet of 100% termites, as opposed to DAS that assumed 8.1%.

DAS Comment: DAS commented that hexaflumuron will not pose a risk to non-target terrestrial plants. DAS stated that because hexaflumuron was initially developed for use on agricultural crops in Europe, data are available to demonstrate the lack of potential crop injury. DAS noted that hexaflumuron’s mode of action (inhi bition of chitin synthesis) is not relevant to plants. DAS also does not beli eve non-target plants will not be exposed to hexaflumuron, given its delivery system.

EPA Response: EPA understands hexaflumuron’s mode of action. Despite knowing the mode of action for insects and animals, there remains no data on the effect(s) (or lack thereof) to plants. EPA encourages DAS to submit the plant t oxicity study referenced in its comments. If the referenced study is submitted, the Agency w ill review and consider it when assessing potential risk to non-target pl ants. The Agency also believe s that DAS has not provided sufficient information to pr eclude exposure of terrestria l plants to hexaflumuron.

Summary of Other Comments by DAS

DAS Comment: DAS provided EPA with comments re garding the use of the hexaflumuron termite baiting system. DAS also noted that while the above-ground termite bait product,

Recruit ®

AG, is registered for use in the US but is not commercially available.

EPA Response : The Agency appreciates the additi onal information on hexaflumuron and intends to revise its problem fo rmulation to reflect the informa tion in the comment. However, the information provided did not significantly al ter the Agency’s understa nding of the potential risk to non-target animals associ ated with the uses of hexaflumuron. The Agency notes that it must assess potential uses unle ss otherwise prohibited by the terms of regist ration. Specifically, regarding DAS’s above ground product, Recruit ® AG, the Agency notes that unless it is cancelled, the Agency will conduct an assessment of this product. Similarly, the hexaflumuron label does not prohibit urban use.

3 This request is voluntary and will not be required via data call

‐ in.9 of 9 DAS Comment: DAS submitted comment regarding the Agency’s conceptual diagram, and risk hypothesis of the problem formulation for re gistration review of hexaflumuron. DAS

commented that it believes hexaflumuron will not pose an ecological risk because it cannot reach ecological receptors in biologically significant concentrations. Because of this, the conceptual diagram proposed by the Agency (i.e., the potenti al risk pathways for a compound based on its formulation(s), and use pattern(s )) is incorrect. DAS also proposed an alternative risk hypothesis.

EPA Response. EPA believes that information and comments submitted by DAS does not preclude the presumption of potential exposure. EPA has noted how it believes that birds may be exposed to all termite cast types and how other non-target organisms including mammals, reptiles, and terrestrial phase amphibians may be potentially exposed. Therefore, EPA does not agree with DAS’s proposed revision of the conceptu al model, or reformulated risk hypothesis. Since EPA believes that DAS has not provided sufficient evidence to preclude exposure, the Agency is requesting effects data in order to determine relevant eff ect levels for different taxa.

Summary of Comments from FIFRA Endangered Species Task Force (FESTF)

Comment: The FIFRA Endangered Species Task Fo rce (FESTF) submitted a comment that the Agency should ensure any company who is a te chnical registrant for hexaflumuron, but not a member of the FESTF (or a company having met its data compensation obligations) provide a formal offer-to-pay to FESTF in conjunction wi th their support of the active ingredient.

Response: The Agency thanks FESTF for its comment and will consider this information as it conducts the registration review and make s its registration review decisions.

Next Steps:

An ecological risk assessment that includes an endangered species assessment will be conducted to support the registration review of hexaflumur on. A human health risk assessment will be required if there are changes in the current us e pattern that warrant such an assessment.

The Agency will develop a DCI for the data gaps listed under the “Risk Assessment and Data

Needs” section above.